Provided is a pagewidth printhead arrangement for an inkjet printer having a print engine controller. The arrangement has a wafer substrate that defines a plurality of ink inlets. A plurality of nozzles each including side walls are located on a wafer substrate with a roof portion attached to said walls to define an ink chamber. The roof portion defines an ejection port. The arrangement also includes an inlet defined in the substrate to supply the ink chamber with ink. A heater element is suspended between the side walls in the ink chamber, so that when electrical actuation energy is applied to respective heater elements, a vapour bubble is formed in the ink leading to a pressure increase in the chamber thereby ejecting the ink via the ejection port. The controller is configured to actuate the heater element to facilitate weighted ink drop volumes to be ejected from the nozzle arrangement.